Problem 9 A differential manometer is used to measure pressure difference between two fluid systems. Two parallel pipes carrying freshwater and seawater are connected to each other by a double U-tube differential manometer, as shown in Figure. (a) Determine the pressure difference between the two pipelines if h = 10 cm. (b) If the pressure difference between the pipes is doubled, what will be the difference in heights (h) of mercury? Take the density of seawater at that location to be 1035 kg/m³, and the specific gravity of the oil is 0.72. Assume all fluids are incompressible. Fresh water Oil 40 cm Sea 80 cm water 50 cm h Mercury